In Barcelona, rumours that the troubled former champion team's Australian lead driver had signed a new deal for 2016 and beyond did the rounds.

"We're talking about it," Ricciardo is quoted by Sky Italia, "but it depends on how things go this year.

"For sure myself and also the team are not here to fight for seventh place," the 25-year-old said in Spain after another disappointing race.

Ricciardo, the only non-Mercedes driver to have won races last year, continued: "We will have to see what happens over the next few months and work hard to make sure we have better performance."

After former team driver Sebastian Vettel and Red Bull won every title on offer between 2010 and 2013, Red Bull is now in a deep trough.

Team boss Christian Horner on Sunday admitted 2015 is already "pretty much a write-off".

Much of the blame is being pinned on struggling engine partner Renault, who turned down the performance of its 'power units' in Spain to prevent another embarrassing spat of blow-ups.

But Horner urged the French marque to simply "go for it".

"Even if you end up using 20 engines," he said, "it is far easier to make a fast engine reliable than a reliable car fast."

But team official Dr Helmut Marko said that even if Renault does take that approach, Red Bull is unlikely to be even close to a podium finish until "Maybe the last three races".

Interestingly, the Austrian also told Kleine Zeitung newspaper that even though a major bodywork package "did not work on the track as it did in the simulator", Red Bull's drivers were also on the back foot in Spain.

"Our established guys need to look out," said Marko, referring to the Red Bull duo of Ricciardo and Daniil Kvyat.

"Paradoxically, the more inexperienced ones did the better job."

He is referring not only to the 17-year-old teen sensation Max Verstappen, but his rookie Toro Rosso teammate Carlos Sainz jr, who qualified an impressive fifth on Saturday.

"The two of them are something extraordinary," said Marko.

"I fought hard for Sainz. He did not have a lot of friends or supporters, but I'm used to that," he added.